It could be a pullet...hard to say but I got some silver laced polish chicks this spring and when their topknots started feathering out my girls' feathers stayed black like yours for a while, whereas my boys had silver in their topknot feathers as soon as they came in. Polish have such crazy personalities! An owl came in my coop and killed all but one of mine a month ago. Here's my guy, Buzzard Chick
She's dying I'm heartbroken. Got some respiratory thing a week ago and been on antibiotics, but it's not fixing her. I imagine she'll be gone by day's end. I'm thinking about taking her to the vet to be euthanized. I can't stand watching....